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991.
Mrcio Jos da Silva Jonh Alexander Vergara Torres Castelo Bandane Vilanculo 《RSC advances》2022,12(19):11796
In this work, vanadium-doped phosphomolybdic acids were evaluated as catalysts in green oxidation routes of terpene alcohols with hydrogen peroxide. A series of phosphomolybdic acids containing a variable load of vanadium cations (i.e., V5+ ions) were synthesized, and tested as catalysts in geraniol oxidation, the model molecule selected. All the catalysts were characterized by powder X-ray diffraction, attenuated diffuse reflectance infrared spectroscopy, UV-Vis spectroscopy, thermogravimetric analysis, N2 adsorption–desorption isotherms, scanning electronic microscopy, X-ray dispersive spectroscopy, and n-butylamine potentiometric titration. Various catalysts were evaluated; phosphomolybdic acids with general formulae H3+nPMo12−nVnO40 (n = 0, 1, 2 and 3), and common Brønsted acids (i.e., H2SO4, H3PO4, and p-toluene sulfonic acid). Among them, vanadium monosubstituted phosphomolybdic acid was the most active catalyst and selective toward epoxide. The effect of main reaction variables, such as temperature, load catalyst, and reactant stoichiometry was assessed. Evaluating the effect of substrate, it was verified that only allylic alcohols such as geraniol and nerol were successfully epoxidized, demonstrating that this is a hydroxy group-assisted reaction. The effect of vanadium doping on the physicochemical properties of the phosphomolybdic acid catalysts was evaluated and used to explain their catalytic performance.The vanadium-doped phosphomolybdic acid (H4PMo11VO40) was the most active and selective heteropoly catalyst in one-pot oxidative esterification of benzaldehyde with hydrogen peroxide. 相似文献
992.
Carolina P. de Souza Melo Catharina B. Campos Juliana de Oliveira Rodrigues Joaquim C. Aguirre‐Neto Ângelo Atalla Mara A. D. Pianovski Edna K. Carbone Luciana B. Q. Lares Hélio Moraes‐Souza Shirlei Octacílio‐Silva Fabiano S. M. Pais Alessandro C. de Souza Ferreira Juliana G. Assumpção 《British journal of haematology》2016,173(2):318-320
Accurate diagnosis of rare inherited anaemias is challenging, requiring a series of complex and expensive laboratory tests. Targeted next‐generation‐sequencing (NGS) has been used to investigate these disorders, but the selection of genes on individual panels has been narrow and the validation strategies used have fallen short of the standards required for clinical use. Clinical‐grade validation of negative results requires the test to distinguish between lack of adequate sequencing reads at the locations of known mutations and a real absence of mutations. To achieve a clinically‐reliable diagnostic test and minimize false‐negative results we developed an open‐source tool (CoverMi) to accurately determine base‐coverage and the ‘discoverability’ of known mutations for every sample. We validated our 33‐gene panel using Sanger sequencing and microarray. Our panel demonstrated 100% specificity and 99·7% sensitivity. We then analysed 57 clinical samples: molecular diagnoses were made in 22/57 (38·6%), corresponding to 32 mutations of which 16 were new. In all cases, accurate molecular diagnosis had a positive impact on clinical management. Using a validated NGS‐based platform for routine molecular diagnosis of previously undiagnosed congenital anaemias is feasible in a clinical diagnostic setting, improves precise diagnosis and enhances management and counselling of the patient and their family. 相似文献
993.
GBT440 increases haemoglobin oxygen affinity,reduces sickling and prolongs RBC half‐life in a murine model of sickle cell disease 下载免费PDF全文
Donna Oksenberg Chihyuan Chuang Zhe Li Qing Xu Abel Silva‐Garcia Chengjing Zhou Athiwat Hutchaleelaha Larysa Patskovska Yury Patskovsky Steven C. Almo Uma Sinha Brian W. Metcalf David R. Archer 《British journal of haematology》2016,175(1):141-153
A major driver of the pathophysiology of sickle cell disease (SCD) is polymerization of deoxygenated haemoglobin S (HbS), which leads to sickling and destruction of red blood cells (RBCs) and end‐organ damage. Pharmacologically increasing the proportion of oxygenated HbS in RBCs may inhibit polymerization, prevent sickling and provide long term disease modification. We report that GBT440, a small molecule which binds to the N‐terminal α chain of Hb, increases HbS affinity for oxygen, delays in vitro HbS polymerization and prevents sickling of RBCs. Moreover, in a murine model of SCD, GBT440 extends the half‐life of RBCs, reduces reticulocyte counts and prevents ex vivo RBC sickling. Importantly, oral dosing of GBT440 in animals demonstrates suitability for once daily dosing in humans and a highly selective partitioning into RBCs, which is a key therapeutic safety attribute. Thus, GBT440 has the potential for clinical use as a disease‐modifying agent in sickle cell patients. 相似文献
994.
Vanessa Fontana Pamela S. Silva Tatiane C. Izidoro-Toledo Celso Biagi Eduardo B. Oliveira Raquel F. Gerlach Jose E. Tanus-Santos 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》2012,26(6):511-519
Purpose
Angiotensin-converting enzyme inhibitors (ACEi) may downregulate matrix metalloproteinases (MMPs). We examined whether enalapril affects MMP-2, MMP-8, and MMP-9 levels and activity, and their endogenous inhibitors (tissue inhibitors of MMPs, TIMP-1 and TIMP-2) levels in hypertensive patients. Moreover, we assessed the effects of enalaprilat on MMP-9 and TIMP-1 secretion by human endothelial cells (HUVECs).Methods
Thirty-eight hypertensive patients received enalapril for 8 weeks and were compared with thirty-eight normotensive controls. Blood samples were collected at baseline and after treatment. Plasma ACE activity was determined by a fluorimetric assay. Plasma MMP-2, MMP-8, MMP-9, TIMP-1, and TIMP-2 were measured by ELISA and gelatin zymography. A fluorogenic peptide cleavage assay was used to measure MMP activity. HUVECs cells were stimulated by phorbol-12-myristate-13-acetate (PMA) and the effects of enalaprilat (10?10 to 10?6?M) on MMP-9 and TIMP-1 levels were determined.Results
Enalapril decreased blood pressure and ACE activity in hypertensive patients (P?<?0.05), but had no effects on plasma MMP-2, MMP-8, MMP-9, TIMP-1, and TIMP-2 levels, or MMP activity. Enalaprilat had no effects on PMA-induced increases in MMP-9 and TIMP-1 secretion by HUVECs or on MMP activity.Conclusions
We show consistent evidence, both in vivo and in vitro, that enalapril does not affect MMPs and TIMPs levels in hypertensive patients.995.
996.
Silva Sara Pereira Beserra-Filho José Ivo Araújo Kubota Melina Chiemi Cardoso Gabriela Nascimento Freitas Francisca Rayanne Silva Gonçalves Bianca Santos Martins Vicente-Silva Wilson Silva-Martins Suellen Custódio-Silva Ana Claúdia Soares-Silva Beatriz Maria-Macêdo Amanda Santos José Ronaldo Estadella Debora Ribeiro Alessandra Mussi 《Metabolic brain disease》2021,36(7):1717-1727
Metabolic Brain Disease - Worldwide, the excessive consumption of fat and/or sugar has increased considerably. Palatable high-fat diets (HFDs) lead to metabolic disturbances and obesity,... 相似文献
997.
Joana Neiva Marisa Passos Silva Gustavo Pires-Morais Adelaide Dias Marta Ponte Daniel Caeiro José Pedro Braga Nuno Ferreira Vasco Ribeiro 《Revista portuguesa de cardiologia》2019,38(3):215-223
Introduction
Single coronary artery (SCA) with no associated congenital heart disease is a rare congenital anomaly. Most cases are asymptomatic and incidental findings, but SCA can cause ischemia, congestive heart failure, and sudden cardiac death (SCD).Case report
A 44-year-old woman presented with Takotsubo cardiomyopathy and cardiogenic shock. Selective cannulation of the left coronary artery (LCA) was not possible on coronary angiography (CA); an SCA was revealed arising from the right sinus, continuing distally as the circumflex artery and thereafter as the left anterior descending artery. Coronary computed tomography angiography (CCTA) confirmed left main atresia and no coronary stenosis. Cardiac magnetic resonance imaging (MRI) showed diffuse myocardial edema and no perfusion defects. The patient's clinical course was favorable under conservative management.Discussion
Our paper describes an incidental finding of right SCA. We report a Lipton type R-I, in which a dominant right SCA supplies the entire myocardium. It is the rarest SCA presentation, with an incidence of 0.0008%; only 15 cases have been reported in the literature, all of which were studied by CA. Of these 15, one had SCD, five angina, one ventricular arrhythmia and one complicated acute coronary syndrome. CCTA confirmed the diagnosis in seven patients, MRI in one and transesophageal echocardiography in another. Nine patients had coronary lesions. Two underwent coronary artery bypass grafting, one percutaneous intervention and 11 conservative treatment.Conclusion
Right SCA with congenital absence of the LCA is one of the rarest coronary artery anomalies. In a significant percentage of patients it is associated with ischemia and can be life-threatening. CCTA and MRI are the modalities of choice for diagnosis and risk stratification. 相似文献998.
Caroline Xavier-Carvalho Renata Duarte da Silva Cezar Naishe Matos Freire Carla Maria Mola de Vasconcelos Victor Edgar Fiestas Solorzano Thiago Gomes de Toledo-Pinto Luciana Gomes Fialho Rodrigo Feliciano do Carmo Luydson Richardson Silva Vasconcelos Marli Tenório Cordeiro Paulo Baptista Elzinandes leal de Azeredo Rivaldo Venâncio da Cunha Luiz José de Souza Antonio Guilherme Pacheco Claire Fernandes Kubelka Patrícia Muniz Mendes Freire de Moura Milton Ozorio Moraes 《Human immunology》2017,78(10):649-656
Outbreaks of the Zika, dengue, and chikungunya viruses, especially in the Americas, pose a global threat due to their rapid spread and difficulty controlling the vector. Extreme phenotypes are often observed, from asymptomatic to severe clinical manifestations, which are well-studied in dengue. Host variations are also important contributors to disease outcomes, and many case-control studies have associated single nucleotide polymorphisms (SNPs) with severe dengue. Here, we found that the TC genotype and T-carriers for SNP rs1285933 in the C-type lectin superfamily member 5 (CLEC5A) gene was associated with severe dengue in a Northern Brazilian population (OR = 2.75 and p-value = 0.01, OR = 2.11 and p-value = 0.04, respectively). We also tested the functional effect of the CLEC5A protein and found that it is upregulated on the surface of human monocytes after in vitro dengue infection. CLEC5A was correlated with viral load inside the monocytes (Spearman r = 0.55, p = 0.008) and TNF production in culture supernatants (Spearman r = 0.72, p = 0.03). Analysis of mRNA in blood samples from DENV4-infected patients exhibiting mild symptoms showed that CLEC5A mRNA expression is correlated with TNF (r = 0.67, p = 0.0001) and other immune mediators. Monocytes from rs1285933 TT/TC individuals showed lower CLEC5A expression compared to CC genotypes. However, in these cells, CLEC5A was not correlated with TNF production. In summary, we confirmed that CLEC5A is genetically associated with dengue severity outcome, playing a central role during the immune response triggered by a dengue viral infection, and rs1285933 is a relevant SNP that is able to regulate signaling pathways after interactions between the dengue virus and CLEC5A receptors. 相似文献
999.
Andressa da Silva Barboza Laura K. Fang Juliana S. Ribeiro Carlos E. Cuevas-Suárez Rafael R. Moraes Rafael G. Lund 《The Journal of prosthetic dentistry》2021,125(4):706.e1-706.e6
Statement of problemThe high recurrence rates of denture stomatitis may be associated with the resistance of biofilms to therapeutics. Therefore, methods that provide biomaterials with antifungal properties are an attractive solution to improving microbial control.PurposeThe purpose of this in vitro study was to modify conventional polymethyl methacrylate (PMMA) through the incorporation of metal methacrylate monomers and to evaluate the physicomechanical and optical properties and antifungal activity of the modified materials.Material and methodsExperimental denture base acrylic resins were fabricated through the addition of zirconium methacrylate (ZM), tin methacrylate (TM), and di-n-butyldimethacrylate-tin (DNBMT) to the liquid of a commercially available denture base PMMA resin. Unmodified PMMA resin was used as the control. The degree of conversion of the materials was tested through Fourier transform infrared spectroscopy (n=3). A digital spectrophotometer was used to assess the color change of the modified materials (n=8). Differences in Knoop hardness and roughness between experimental groups were also evaluated (n=8). A biofilm accumulation test with Candida albicans (ATCC 62342) (n=4) was performed for 5 days in Sabouraud broth culture supplemented with 10% sucrose. Data were subjected to analysis of variance and the post hoc Tukey honestly significant difference test (α=.05).ResultsThe degree of conversion and color-change values of the experimental materials were statistically similar to those of the control (P=.593). The incorporation of DNBMT significantly increased the hardness of the modified material (P=.014). The ZM, TM, and DNBMT groups had higher antifungal activity against C. albicans (P=.001) and lower roughness than the control group (control 0.65 ±0.05 μm; ZM 0.34 ±0.09 μm, TM 0.34 ±0.11 μm, and DNBMT 0.41 ±0.08 μm).ConclusionsThe metal-containing methacrylate monomers provided antifungal action to the modified materials without affecting the physicomechanical or optical properties of the denture base resin. ZM, TM, and DNBMT are potential reactive agents for the fabrication of PMMA denture base resins with antifungal properties. 相似文献
1000.
Joana Barros Marlei G. Silva Isabela N. Rôças Lucio S. Gonçalves Flávio F. Alves Maria A. Lopes Irene Pina-Vaz José F. Siqueira Jr. 《Journal of endodontics》2014